Rainfall

Rainfall totals exceeded their long-term averages at all stations for the first time in a number of years. For Melbourne Regional Office, the official station for Melbourne, this was the first time since 1996 an above average annual total was recorded. The annual totals were also the highest for a number years. Totals for 2010 ranged from 558.0 mm at Avalon Airport to 1026.8 mm at Coldstream. Scoresby Research Institute had the smallest anomaly, receiving just above normal rainfall while Coldstream had the largest anomaly, receiving one and a half times their normal rainfall. The wettest single day was 31 October when Ferny Creek (Dunns Hill) received 75.6 mm, several other sites recorded their wettest daily total for the year on 31 October. Coldstream and Viewbank (ARPANSA) recorded their wettest year ever.

Maximum temperature

Average maximum temperatures for 2010 ranged from 15.5 °C at Ferny Creek (Dunns Hill) to 21.0 at Melbourne Regional Office. Viewbank (ARPANSA) had the coolest anomaly, -0.3 °C, while Essendon Airport had the warmest with 0.7 °C. The hottest day was 11 January when Avalon Airport sweltered through 45.7 °C, several other sites recorded their hottest day on 11 January. The coldest day was 29 June when Ferny Creek (Dunns Hill) recorded a maximum temperature of only 4.9 °C. No stations recorded either their highest or lowest average maximum temperatures during 2010.

Minimum temperature

Average minimum temperatures for 2010 ranged from 8.2 °C at Coldstream to 12.1 °C at Melbourne Regional Office. Viewbank (ARPANSA) and Ferny Creek (Dunns Hill) had the smallest anomalies, 0.3 °C above the long-term average, while Melbourne Regional Office had the largest, 1.9 °C. The coldest night was 9 July when Coldstream shivered through -3.2 °C. The warmest night was 12 January when Melbourne Airport recorded 28.8 °C, several other stations also recorded their warmest night for the year on 12 January. Melbourne Regional Office recorded its equal highest overnight minimum
temperature during the night of January 12th to 13th of 30.6 °C.

Wind

The strongest wind gusts were 102 km/h recorded at Melbourne Airport on 6 March and at Laverton RAAF on 5 Sep.

Severe thunderstorms

On March 6 severe thunderstorms developed to the northwest of the Melbourne metropolitan area and moved through the city from early afternoon, progressing to the eastern suburbs. Widespread flash flooding and water damage to property occurred across the CBD and the eastern suburbs with extensive hail damage to cars and property. The largest hailstones, 10 cm, were reported in the Ferntree Gully area.

Warm spell

Melbourne Regional Office recorded a warm spell of maximum temperatures above 20.0 °C that lasted for 123 consecutive days from 9 December 2009 to 10 April 2010. This was the longest run of maximum temperatures above 20.0 °C on record. The previous longest warm spell of maximum temperatures above 20.0 °C only lasted 78 days.

Cool spell

Melbourne Regional Office recorded a cool spell of maximum temperatures below 20.0 °C that lasted for 138 consecutive days from 11 May to 25 September. This was the longest run of maximum temperatures below 20.0 °C since 1992.

Notes

An Annual Climate Summary is prepared to list the main features of the weather in Melbourne Metropolitan Area and Environs using the most timely and accurate information available on the date of publication; it will generally not be updated. Later information, including data that has had greater opportunity for quality control, will be presented in the Monthly Weather Review, usually published in the fourth week of the month.

This statement has been prepared based on information available at
9 am on Tuesday 4 January 2011.
Some checks have been made on the data, but it is possible that results will change
as new information becomes available.

Averages are long-term means based on observations from
all available years of record, which vary widely from site to site.
They are not shown for sites with less than 10 years of record, as they cannot then be calculated reliably.
The median
is sometimes more representative than the
mean
of long-term average rain.

The Rank indicates how rainfall this time compares with the climate record for the site,
based on the
decile ranking
(very low rainfall is in decile 1, low in decile 2 or 3,
average in decile 4 to 7, high in decile 8 or 9
and very high is in decile 10).
The Fraction of average shows how much rain has fallen this time as a
percentage of the long-term mean.